This invention relates to pipe coupling means, and more particularly, to pipe coupling means of the type which utilize a male-female type connection and seal means disposed therebetween.
One system for irrigating land utilizes a selectively drivable wheeled mover unit. An elongated irrigation line, made up of a plurality of pipe sections connected end to end by coupling means, is positioned transversely of and associated with the mover unit. The irrigation line is also supported along its overall length at spaced intervals by wheels fixed thereto.
Generally, the irrigation line has secured thereto a plurality of sprinkler nozzles, which are properly placed relative to the irrigation line so that each is initially positioned substantially upright. Water passing through the line exits from such sprinkler nozzles to properly irrigate an area of land. Upon completion of such irrigation of that area, the mover unit is actuated and moved to another area of land. The line is associated with the mover unit in such a manner as to act as a driving axle which rotates the wheels supporting it along its length. The irrigation line rotates as a unit so that the mover unit may be stopped in a chosen position to in turn position the nozzles against substantially upright. This area of land is now irrigated in the manner previously described.
Coupling means used to couple such pipes end to end, it will be seen, are subjected to a relatively great torque during such operation, since the irrigation line acts as a driving axle as described above. Thus, such coupling means must be capable of properly operating when subjected to such torque. Additionally, the coupling means should enable the pipe sections to be easily and quickly attached and detached from the couplings which join them. The coupling means joining any pair of pipes should, of course, provide an effective fluid-tight joint, in addition to the above-mentioned attachment and detachment feature. Consequently, the coupling means should be particularly designed with these features in mind. Additionally, the coupling means should be capable of effective coupling even though a degree of linear or rotational misalignment between the pipes exists. And, such coupling means should be capable of positionally securing one pipe relative to another when in use.
A common type of pipe coupling includes an annular seal disposed between adjacent radial surfaces of the pipe sections to be coupled. Such a system does not generally allow for a degree of linear or rotational misalignment between the pipe members, nor is such system capable of providing highly efficient sealing when the irrigation pipe is rotated to subject the coupling to a rotational torque.